JPH04354539A - Catalytic activity gel - Google Patents

Abstract

PURPOSE: To provide amorphous gel exhibiting a catalyst activity in various reactions according to a supported metal oxide. CONSTITUTION: A soln. comprising (1) tetraalkyl ammonium hydride in which an alkyl group is an ethyl group, n-propyl group or n-butyl group, (2) a soluble silicon compd. to be hydrolyzed into SiO2 , and (3) one or more soluble salt or acid of metal is prepared. The obtained soln. is heated and gellated. Gel is dried and calcined at first in the atmosphere and then in an oxidizing atmosphere, to prepare amorphous gel having a catalyst activity.

Description

[Detailed description of the invention]

The present invention relates to a catalytically active gel consisting of a silica matrix in which one or more catalytically active metal oxides are dispersed. The invention also relates to the use of this gel as a catalyst.

Certain amorphous silica-alumina gels with catalytic activity are known in the art. For example, European Patent Application No. 160,145 describes amorphous silica-alumina in which the average pore diameter is typically 50 to 500 Å and the silica/alumina ratio is typically 1/1 to 10/1. A process for the alkylation of aromatic hydrocarbons is disclosed. M. R. S. Manton and J.
．． C. Davidtz is the Journal of Ca
taxis, 60, pp. 156-166 (197
9) describes a method for the synthesis of amorphous silica-alumina catalysts with controlled pore volume. These catalysts are typically 3.7 to 15 nm (37 to 1
50 Å) in diameter. Italian patents 1 and 2
No. 19,692 discloses a silica-alumina gel that is amorphous by X-ray analysis, microporous, and has catalytic activity.

[0003] The inventors have discovered that one or more metal oxides are uniformly dispersed, forming monomodal pores (approximately 10 Å in diameter) within the microporous region.
) We have newly discovered a catalytically active gel consisting of a matrix having the following properties, leading to the present invention. This gel exhibits catalytic activity in different reactions (mainly oxidation reactions and acid-catalyzed reactions) depending on the various oxides contained therein. According to this, the present invention has a catalytic activity in an acid-catalyzed reaction or an oxidation reaction; a silica matrix in which oxides of one or more metals having a homogeneous distribution; monomodal pores and large surface area within the microporous region; a molar ratio of SiO2/metal oxide of 5/1; or 300
The present invention provides a gel that is amorphous on X-ray analysis and has a particle size of /1. The gel comprises (a) (1) a tetraalkylammonium hydroxide (TAA-OH) in which the alkyl group is selected from ethyl, n-propyl, and n-butyl;
); (2) a soluble silicon compound that is hydrolyzed to SiO2; (3) one or more soluble salts or acids of one or more metals (the oxides of which exhibit catalytic activity); The ratio is between 5/1 and 300/1, and TAA
-OH/SiO2 molar ratio is 0.05/1 to 0.5
/1 and the molar ratio of H2O/SiO2 is 5/1 to 40/1; (b) heating the solution thus obtained; (c) drying the gel; (d) calcining the dried gel first in an inert atmosphere and then in an oxidizing atmosphere.

In step (a) of the above operation, tetra-
The use of ethyl, n-propyl or n-butylammonium hydroxide is important. In this regard, the use of homologous ammonium compounds, such as tetramethylammonium hydroxide,
e) leading to the formation of a gel with Step (a) of the method
The soluble silicon compound used in is preferably a tetraalkyl silicate, such as tetraethyl silicate. The water-soluble salts or acids of one or more metals, the oxides of which exhibit catalytic activity, especially in the acid and oxidation-catalyzed form, are selected from water-soluble or hydrolyzable salts and acids of the metals in question. The operation of step (a) of the method is carried out at room temperature (20-2
5° C.) or at a temperature higher than room temperature and lower than the gel initiation temperature (about 50° C.). The order in which the water-soluble components are added in step (a) is not critical. However, it is preferable to first prepare an aqueous solution containing a soluble compound of the metal in which the tetraalkylammonium hydroxide and its oxide exhibit catalytic activity, and then add the soluble silicon compound to this aqueous solution. Water-alcoholic solutions containing aqueous components can also be used in step (a). In either case, the molar ratios of the constituents in the resulting aqueous solution must be as follows: SiO2/metal oxide 5/1 to 300/1 TAA-OH/SiO2
0.05/1 to 0.5/1H2O/S
iO2 5/1 to 40/1 These molar ratios are preferably as follows. SiO2/metal oxide 10/1 to 200/1 TAA-OH/SiO2
0.1/1 to 0.3/1H2O/S
iO2 10/1 to 25/1

Gelation in step (b) of the preparation process is carried out by heating the solution to a temperature of 50 to 70°C, preferably about 60°C. The time it takes for gelation to complete varies depending on temperature, concentration, and other factors, but typically ranges from 15 minutes to 5 hours, typically about 25 to 60 minutes. Importantly, gelation takes place simply by heating the solution. In this regard, if gelation is carried out under acidic conditions, as in known methods, gels are produced which have unfavorable characteristics, particularly with regard to porosity and pore size distribution. The gel thus obtained is dried in step (c) of the method of the invention. This drying process is suitably carried out at a temperature below 150°C, preferably from about 90 to 100°C, for a period of time sufficient to completely or substantially completely remove moisture. In one embodiment of the method of the invention, the drying in step (c) is carried out by a spray drying method. In this case, a spray dryer operated at a gas inlet temperature of 230 to 250°C and an outlet temperature of 140 to 160°C can be used;
The gel is injected into the dryer in the form of droplets and these droplets are brought into contact with an inert gas. In each case, the gel is calcined in step (d) of the method of the invention. This calcination is preferably carried out first in an inert atmosphere such as nitrogen and then in an oxidizing atmosphere such as air. The calcination temperature is suitably between 500 and 700°C, preferably about 500°C.
to 600°C. Calcination times vary from 4 to 20 hours, but are typically about 6 to 16 hours.

The catalytically active silica gel of the invention thus obtained has a structure that is completely amorphous in X-ray analysis, and the SiO2/metal oxide ratio is similar to that of the initially supplied silicon and other metals. The ratio of the compounds is equal and has the characteristic of being between 5/1 and 300/1, preferably between 10/1 and 200/1. This metal silica gel has a large surface area of 560 to 1000 m2/g (BET determination). The total volume of the pores is 0.3 to 0.6 ml/g. The pores have an average diameter of about 10 Å or less, falling within the narrow size distribution of micropores. In particular, pores with a diameter of 30 Å or more are absent or substantially absent. Additionally, pores with a diameter of 20 Å or more are generally absent. The metal-silica gels of the present invention have catalytic activity, and the type of catalytic activity depends on the type of oxide attached. For example, metal-silica gels containing oxides of one or more metals selected from molybdenum, titanium, and vanadium are active in the epoxidation of olefins to cycloolefins. Metal-silica gels containing molybdenum and vanadium are likewise active in the oxidation of amines to oximes, and metal-silica gels containing potassium or iron are active in the oligomerization of olefins. Metal-silica gels containing zirconium, molybdenum, vanadium or chromium, or mixtures thereof, are preferably active in the hydroxylation of phenol to pyrocatechol and hydroquinone. In order to further explain the invention, some examples are illustrated below.

Example 1 Gallium Silica Gel 38 g of a 30% by weight aqueous solution of tetrapropylammonium hydroxide was introduced into a 400 cc beaker made of Pyrex glass equipped with a magnetic stirrer and placed on a stirring/heating plate. Add this aqueous solution to 26.7 ml of water.
Ga(NO3)3.8H2O 1.33 diluted with cc
g was added. The mixture was then heated to approximately 55°C and 34.7g of tetraethylsilicate was added to the clear warm aqueous solution. The mixture was stirred until the system gelled, typically about 1 hour after adding the ethyl silicate, producing a completely clear, dense gel (no longer stirrable). The gel was then left to age for 48 hours at ambient temperature and transferred to a flask (1 liter) on a rotary evaporator.
I put it in. The temperature of the constant temperature bath of the evaporator was adjusted to approximately 90° C., the flask was rotated at maximum speed, and a light stream of air was passed over the sample to promote drying under atmospheric pressure. These conditions were maintained for 3-4 hours. The resulting sample was then placed in an oven at 100°C for 1 hour. The dry gel thus obtained was calcined in nitrogen at 550 °C for 3 hours (to remove most of the organic matter trapped in the solid by pyrolysis) and then the unburnt residual carbon was removed by burning in air at 600°C for 10 hours. The obtained gallium silica gel (11.2 g) had the following characteristics. Surface area: 823 m2/g Pore volume: 0.32 cm3/g The average diameter of the pores (BET) was about 10 Å or less, and there were no pores with a diameter of 20 Å or more.

Example 2 Tin silica gel 148.3 g of water, 31.3 g of tetrapropylammonium hydroxide and (NH4)2SnCl6 4
Tetraethyl silicate in an aqueous solution consisting of 104.g.
Tin silica gel (32.3 g) was prepared by adding 1 g. The operation was performed as described in Example 1.

Example 3 Titanium Silica Gel Titanium silica gel was prepared as follows. A mixture consisting of 104.1 g of tetraethyl silicate and 4.5 g of tetraethylorthotitanate was mixed with 103 g of water.
．． 8g and tetrapropylammonium hydroxide
was added to an aqueous solution containing 31.3 g. After about 2 hours,
A homogeneous, transparent yellow gel was formed. The resulting gel was dried in a rotary evaporator at 100° C. under a stream of nitrogen. It was then calcined at 550°C for 1 hour in nitrogen and 10 hours in air. 31.9 g of gel was obtained.

Example 4 Vanadium silica gel tetrapropylammonium hydroxide 53g
(29.89%: titer) and a solution containing 55 g of water,
A second solution containing 2.3 g of NH4VO3 and 104 g of tetraethylorthosilicate was added to prepare vanadium silica gel (32.1 g). The operation was performed in the same manner as in Example 1.

Example 5 Chromium Silica Gel According to the procedure described in Example 1, Cr(NO3)3 was added to a mixture of 73 g (29.89% titration) of tetrapropylammonium hydroxide and 55 g of water.
- 33.3 g of chromium silica gel was prepared by adding a second mixture consisting of 4 g of 9H2O, 50 g of ethanol and 104 g of tetraethylsilicate.

Example 6 Iron Silica Gel Following the same procedure as in Example 1, 50 g of ethanol was added to a solution containing 73 g of tetrapropylammonium hydroxide (29.89% titration) and 55 g of water.
This gel (31.8 g) was prepared by adding a second solution containing g, 4 g of Fe(NO3)3.9H2O and 104 g of tetraethylsilicate.

Example 7 Zirconium Silica Gel Following the same procedure as in Example 1, 50 g of water and 85 g of tetrapropylammonium hydroxide (29
．． A solution containing Zr(OC3H
7) 4 6.5g and tetraethyl silicate 104
This gel (34.0
g) was prepared.

Example 8 Molybdenum silica gel tetrapropylammonium hydroxide 53g
(28.89%: titer) and 3.4 g of molybdic acid were added to a second solution containing 55 g of water and 104 g of tetraethylsilicate to obtain this gel (
35.8g) was prepared.

Example 9 Zinc silica gel 104 g of tetraethyl silicate and then 2.7 g of ZnCl2 in 50 g of ethanol were added to 30 g of water.
70g of tetrapropylammonium hydroxide inside
(29.89%: titer). Zinc silica gel was treated in the same manner as in Example 1. 34.
3g was obtained.

Example 10 Cobalt silica gel tetrapropylammonium hydroxide 81g
(29.89%: titration amount) in 30 g of water.
3) Added to a solution containing 5.8 g of 2.6H2O. Chromatographically pure air washed with 3M NaOH for 24 hours was bubbled through very slowly. Then,
Adding 104g of tetraethylsilicate, Example 1
Perform the same operation as above, and finally cobalt silica gel 3
0.6g was obtained.

Example 11 Titanium/molybdenum silica gel 3.4 g of molybdic acid, 80 g of tetrapropylammonium hydroxide (28% titration) and 60 g of water
A solution was prepared containing g. 104 g of tetraethyl silicate and 4.5 g of tetraethylorthotitanate were then added to this solution. By performing the same operation as in Example 1, titanium/molybdenum silica gel 35.7
I got g.

Example 12 Phosphorus/vanadium silica gel tetrapropylammonium hydroxide 70g
(28%: titration amount), 2.9 g of 85% phosphoric acid and NH4
A solution containing 2.3 g of VO3 was prepared. Then,
38 g of water and 104 g of tetraethylsilicate were added to this solution. Phosphorus/vanadium silica gel with a surface area of 603 m2/g was prepared in the same manner as in Example 1.32.
58g was obtained.

Example 13 Iron/Titanium Silica Gel Tetrapropylammonium Hydroxide 75g
(28%: titer) and 55 g of water were prepared. Tetraethyl silicate 104g, tetraethylorthotitanate 4.5g and ethanol 50g
A solution containing 4 g of Fe(NO3)3.9H2O was added thereto. The same operation as in Example 1 was carried out to obtain 32.3 g of iron/titanium silica gel.

Example 14 Catalytic Activity of Molybdenum Silica Gel The catalytic activity of molybdenum silica gel prepared as in Example 8 was investigated by epoxidation of various olefins with tertiary butyl hydroperoxide (TBHP) and by hydrogen peroxide and TBHP. The oxidation of cyclohexylamine to cyclohexyloxime was tested. Example 14a Epoxidation of cyclohexene Cyclohexene 810 mg (9.88 mmol)
and molybdenum silica gel were weighed into a bottle equipped with a screw stopper with a perforated rubber septum. Bottle (equipped with anchor-type magnetic stirrer)
was sealed and placed in a perforated aluminum block. The block was heated to 85°C and after 30 minutes, 80% concentration of TB was added.
1.41 g (12.5 mmol) of HP was added via syringe. The progress of the reaction was followed by gas chromatographic analysis (with internal standard). The following results were obtained.
Conversion rate
Selectivity After 18 hours at 25°C: Cyclohexene 30.2% 100
%
TBHP 30.9%
77% After 18 hours at 60°C:
Cyclohexene 45.0%
100%
TBHP 5
7.7% 62% 18 at 85℃
After hours: Cyclohexene 71.3%
100%
TBHP
95.0% 58% Example 14b Epoxidation of 1-octene Using a procedure similar to Example 14a, 40 mg of molybdenum silica gel, 730 mg of 1-octene (
6.51 mmol) and 80% concentration of TBHP 90m
g (0.8 mmol) was subjected to the reaction. 100 to 1
After reacting at 10° C. for 1 hour, the conversion rate of TBHP was 69.2%, the selectivity was 13.4%, and the yield and selectivity of epoxide were 9.3%.

Example 14c Epoxidation of 2-cyclohexen-1-ol Using a procedure similar to Example 14a, 40 mg of molybdenum silica gel, 2-cyclohexen-1-ol 1
．． 0 g (10.2 mmol) and 80% concentration of TBHP
1.18 g (10.5 mmol) was used for the reaction. 8
After carrying out the reaction at 0° C. for 2 hours, the olefin conversion rate was 66%, the epoxide yield was 82%, the TBHP conversion rate was 60%, and the selectivity was 87%. Example 14d Oxidation of cyclohexylamine with TBHP 860 mg (8.24 mmol) of cyclohexylamine, 40 mg of catalyst and 1.07 g of 80% strength TBHP were fed into a flask. After 2 hours at 80°C, the conversion of TBHP was 64% and the conversion of cyclohexylamine was 30%.
, the yield of oxime was 5%. Example 14e Oxidation of cyclohexylamine with hydrogen peroxide Cyclohexylamine 860 mg (8.24 mmol),
1.6 ml (16.48 mmol) of 30% H2O2 and 40 mg of catalyst were charged to the flask. After 2 hours at 85°C, amine conversion was 16% and oxime yield was 8%.
, the selectivity of oxime to substrate was 50%. Example 14f Hydroxylation of phenol 25 g phenol, 2.5 ml water and 0.3 catalyst
g was fed into the flask. 100 while stirring the suspension.
heated to ℃. Then 6 ml of 33% H2O2 was slowly added dropwise. At the end of the reaction, the catalyst was separated and the reaction products were analyzed by gas chromatography. After 30 minutes at this temperature, H
The conversion rate of 2O2 was 100%, and the yield of pyrocatechol + hydroquinone was 19%.

Example 15 Catalytic Activity of Vanadium Silica Gel The catalytic activity of vanadium silica gel prepared as described in Example 4 was tested for the epoxidation of various olefins and the hydroxylation of phenols. Example 15a Epoxidation of Cyclohexene Using a procedure similar to Example 14a, 810 mg (9.88 mmol) of cyclohexene, 40 mg of vanadium silica gel and 1.41 g of 80% TBHP
(12.5 mmol) was used for the reaction. The following results were obtained.
Conversion rate
Selectivity After 18 hours at 25°C: Cyclohexene 4.1% 100
%
TBHP 13.3%
24% After 18 hours at 60°C:
Cyclohexene 44.1%
100%
TBHP 5
2.0% 68% 18 at 85℃
After hours: Cyclohexene 57.0%
100%
TBHP
65.3% 68% Example 15b Epoxidation of 1-octene Using a procedure similar to Example 14a, 40 mg vanadium silica gel, 730 mg 1-octene (
6.51 mmol) and 80% concentration of TBHP 90m
g (0.8 mmol) was subjected to the reaction. 100 to 1
After carrying out the reaction at 10° C. for 1 hour, the conversion rate of TBHP was 36% and the selectivity was 86%. Example 15c Hydroxylation of Phenol 25 g of phenol, 2.5 ml of H2O and 0.3 g of catalyst were charged to a flask. The suspension was heated to 100° C. with stirring. Then 33% (w/v) H2O
26 ml was slowly added dropwise. At the end of the reaction, the catalyst was separated and analyzed by gas chromatography using a column (length 1.8 m) packed with 10% SP2250. After 150 minutes at this temperature, the conversion of H2O2 was 11% and the yield of pyrocatechol + hydroquinone was 20%.
%Met. Example 15d Oxidation of cyclohexylamine with TBHP 860 mg (8.24 mmol) cyclohexylamine, 40 mg catalyst and 1.07 g (9
．． 52 mmol) was fed to the flask. 2 at 80℃
After hours, the conversion of TBHP was 78%, the conversion of cyclohexylamine was 16%, and the yield of oxime was 2%.

Example 16 Catalytic Activity of Titanium Silica Gel Example 16a Epoxidation of 1-Octene Using a procedure similar to Example 15a, 15.2 mmol of 1-octene was prepared as described in Example 3. Prepared titanium silica gel 50mg and 80% TBH
2.5 mmol of P was used in the reaction. After 1 hour at 110°C, the conversion of 1-octene was 3.9%, the conversion of TBHP was 27%, and the selectivity of TBHP was 87%. Instead of the above, 1-octene 33 mmol, 80%
When 5 moles of TBHP and 15 mg of catalyst were subjected to the reaction, the conversion rate of 1-octene was 2 after 240 minutes at 110°C.
．． 4%, TBHP conversion rate was 26%, and TBHP selectivity was 60%.

Example 17 Activity of Titanium/Molybdenum Silica Gel Example 17a Epoxidation of Cyclohexene Using a procedure similar to Example 15a, 9.88 mmol of cyclohexene, titanium prepared as described in Example 11. /Molybdenum silica gel 40mg,
and 12.5 mmol of 80% TBHP were subjected to the reaction. After 18 hours at 85°C, the conversion of cyclohexene was 5.
8%, its selectivity is 100%, and the conversion rate of TBHP is 61
%, and the selectivity was 95%. Example 17b Epoxidation of 1-Octene Using a procedure similar to Example 15a, 6.5 mmol of 1-octene, 0.8 mmol of 80% TBHP and 40 mg of titanium/molybdenum silica gel were subjected to the reaction. After 1 hour at 110°C, the conversion rate of 1-octene was 39.9%, the conversion rate of TBHP was 47.6%, and the conversion rate of TBHP was 47.6%.
The selectivity of HP was 83.8%.

Example 18 Activity of gallium silica gel Example 18a Oligomerization of 1-octene 6 ml of anhydrous 1-octene and previously dried at 400° C. for 3 hours (prepared as described in Example 1) Approximately 30ml containing 0.4g of catalyst and thermocouple
volume glass pressure vessel. Temperature 15 of the suspension
Heated to 0°C for 3 hours. After cooling, the catalyst was separated and the reaction products were analyzed by gas chromatography using a column (length 1.2 m) packed with 3% SP2100 (up to 100°C for 5 min, then at 25°C/ up to 280°C). Octene was 57.1% (percentage of gas chromatography area), dimer was 33.4%, trimer was 6.9%, and tetramer was 2.6%. Example 18b Alkylation of Benzene Working as described in Example 18a, 1.45 g of 1-octene, 10 cc of benzene and 0.0378 g of n-decane (as gas chromatography internal standard)
g was subjected to the reaction. After 3 hours at 150°C, 9.69 mmol of octene and 3.20 mmol of alkylate remained.

Example 19 Activity of iron silica gel Example 19a Oligomerization of 1-octene The anhydrous 1-octene was prepared as described in Example 18a.
6 ml of octene and 0.4 g of catalyst prepared as described in Example 6 were subjected to the reaction. After 3 hours at 200°C, octene was 91.0% (percentage of gas chromatography area) and dimer was 9.0%. Example 19b Alkylation of Benzene Working as described in Example 18a, 1.45 g of 1-octene, 10 cc of benzene and n-decane (
(as gas chromatography internal standard) 0.0370g
was subjected to the reaction. After 3 hours at 150°C, 12.54 mmol of octene and 0.41 mmol of alkylate remained. Example 20 Activity of Zirconium Silica Gel in the Hydroxylation of Phenol Working as described in Example 15c and using the catalyst prepared as in Example 7, after 3 hours at 100°C, the conversion of H2O2 was The yield of pyrocatechol + hydroquinone was 19%. Example 21 Activity of chromium silica gel Working as described in Example 15c and using catalyst prepared as in Example 5, after 2 hours at 100°C, conversion of H2O2 was 100%, pyrocatechol The yield of +hydroquinone was 25%.

Claims (13)

[Claims] Claim 1: Having catalytic activity in an acid-catalyzed reaction or oxidation reaction; one or more having catalytic activity selected from titanium, gallium, chromium, iron, zirconium, vanadium, molybdenum, zinc, cobalt, phosphorus, and tin. consisting of a silica matrix in which oxides of metals are uniformly dispersed;
having monomodal pores and large surface area within the microporous region;
The molar ratio of SiO2/metal oxide is 5/1 to 300/
1, which is amorphous on X-ray analysis, the gel having
(a) (1) Tetraalkylammonium hydroxide (TAA-OH) in which the alkyl group is selected from ethyl, n-propyl, and n-butyl;
2) Soluble silicon compound hydrolyzed to SiO2; (
3) One or more metals (its oxide exhibits catalytic activity)
one or more soluble salts or acids with a SiO2/metal oxide molar ratio of 5/1 to 300/1, TAA-OH
/SiO2 molar ratio is 0.05/1 to 0.5/1, and H2O/SiO2 molar ratio is 5/1 to 40/
prepare an aqueous solution containing each of the above components in an amount equal to 1; (b) heat the solution thus obtained to form a gel; (c) dry the gel; (d) first Catalytically active gel, characterized in that it is obtained by calcining the dry gel in an active atmosphere and then in an oxidizing atmosphere. 2. The method according to claim 1, wherein the step (
The soluble silicon compound in a) is a tetraalkyl silicate, and the water-soluble salt or acid of one or more metals whose oxide exhibits catalytic activity, especially in the acid form and oxidation catalyst form, is a water-soluble or hydrolyzable metal. Catalytically active gels selected from salts and acids. 3. A catalytically active gel according to claim 2, wherein the soluble silicon compound is tetraethyl silicate. 4. The method according to claim 1, wherein the step (
For a), the aqueous solution components have a SiO2/metal oxide molar ratio of 10/1 to 200/1, and T
The molar ratio of AA-OH/SiO2 is 0.1/1 to 0.
3/1 and the catalytically active gel is present in an amount in which the H2O/SiO2 molar ratio is between 10/1 and 25/1. 5. The method according to claim 1, wherein the step (
A catalytically active gel in which the operation a) is carried out at room temperature (20-25°C) or at a temperature above room temperature and below the gel initiation temperature (about 50°C). 6. The method according to claim 1, wherein the step (
For b), a catalytically active gel is gelled at 50 to 70°C for a treatment time of 15 minutes to 5 hours. 7. A catalytically active gel according to claim 6, wherein gelation is carried out at a temperature of 60° C. and a treatment time of 25 to 60 minutes. 8. The method according to claim 1, wherein the step (
Catalytically active gel, wherein drying of c) is carried out at a temperature below 150°C. 9. A catalytically active gel according to claim 8, wherein drying is carried out at a temperature of about 90 to 100°C. 10. The catalytically active gel according to claim 1, wherein the drying in step (c) is carried out by a spray drying method. 11. A catalytically active gel according to claim 1, wherein the calcination in step (d) is carried out at a temperature of 500 to 700° C. and a treatment time of 4 to 20 hours. 12. The method of claim 11, wherein the calcination of step (d) is carried out at about 550-600°C.
Catalytically active gel, run for 6 hours. 13. Use of gels according to claims 1-12 in catalytic reaction processes, in particular in the epoxidation of olefins and cycloolefins, in the oxidation of amines, in the oligomerization of olefins and in the hydroxylation of phenols.